Record-disk for telegraphones.



J.. A. LIER. moan msx ron. Tmaannom..

LIPLI'QATIOI. FILED IAB. 25,

'Patented Desch 22, 1908.

] no@ n fo a Hozuegj JOHN A.' LIEB, OF NEW YORK, NI'Y.,

ASSIGNOR TOAMERICAN TE'iLEGRArnoNE OOMPANY, A p

i VCORPORATION O F THE; DISTRICT 4OF COLUMBIA.

' .nEconn-Drsx Fon TELEGRAPHoN-Es.

Specification of Letters Patenti Application ledlarch 25, 1907. B 'eral No: 3649509.v

'Patented me. 2 2, loos.

To all whom it may concern:

-of the United States, residin at the city of New Yrk, inthe -borough o Brooklyn and State of New York, have invented certain new and useful Improvements in Record- Disks forTele aphones, of which the following isy a full, c ear, and exact description.

= My invention relates to an improvement in "'ftherecording diskswhich are used with the telegraphone, and in which a magnetic sound record 1s made by magnetizing the steel in a spiral path under the influence of an electromagnet in a telephone circuit. For this purpose plain -steel disks have been used, butit 1s necessary with a ilat or plane disk to have a se arate and special guiding means .for movin `the electromagnet radially over the face o the disk as the latter rotates. It is evident that in case of wear, or certain im lperfections in the mechanism, the ,path

tracedfin the reproduction may not exactly accord to that of the recording operation.

4Moreover, in case the disk is removed from one machine to be used in another, or in case 1t -1s attempted to use a number of records wlth one machine 1n successlon, the placlng i and readjustment of the disks may not be lployed therefor.

pro erly made. For these reasons it isde sira le to have the u iding means on the face of the disk itself. In carrying out my invention I secure this result irf a very simple 'and' easy way by spirally winding a steel strip or wire so as to produce a built-up disk with a' flat'face. This construction has certain additional. advantages from the stand oint of` e later which w1l1 be self supporting vwhen wound ina spiral coil. A convenient form for this purpose is 'that shown in Fig. 3, which the wire-Tis convex on one side 8, and concave on the other side '9. The side edges 10 of a Beit known that I, JOHN A. LIEB, a citizen etic reproduction disk em,

Wire or .strip of this form comesubstantially to an. apex or point, although this is, of course, not essential. With this form of the invention. it is merely necessary to obtain a supporting core or member -11, and wind the strip 7 spirally thereabout, until a disk of the required sizeis'produced. This is best done between guiding plates so as to keep the alinement erfect. Finally, when the coil or disk is of t e re 4uired size, a band 12 of Babbitt metal or ot er material is shrunk about its' eripheral edge so as to tightly clamp all of t e convolutions into a compact or unitary disk or structure.

--With the form of the invention as above described a steel disk is finally produced in which the -face has a continuous guiding thread or spiral edge due to the wire convo` lutions. vIt is evident that this thread or i spiral may be madethe guidingmeans of the recording and reproducing devlces in exactly the same wa as the spiral grooves of an ordinary grap Ophone disk are used. The

magnetic record is made in the steel Wire in accordance with the Well known telegraphone principle. In practice the records obtained by a built-up dislf of this form are very eiiiclent for the purposes of reproduction, since the successive spirals or convolutions, being separated from one another by an air gap ex# cept for a slight imperfect contacting line-Or area, do not exert a de-magnetizing action on .one another.

l1. A record-receiving body for telegraphones consisting of wire of magnetic mate rial wound in spiral form with theadjacent convolutions interlocking 'with each other.

2. A record-receiving body for telegraphones consisting of a Wire or strip having opposite concave and convex sides Wound into a spiral in which the convex side of one convolution is seated in the concave side of another.

3. A record-receiving body for telegraphones consisting of a Wire or strip with sharp edges having opposite concave and! convex sides wound into a spiral in which the convex side of one convolution is seated in convex sides Wound into a spiral in which the t convex side of one convolution is seated in the concave side of another, and an outside clamp holding the convolutions together.'

5. A built-up disk for a telegraphone, comprising spirally coiled steel wlre,l the various convolutions of which interlock With one another.

6. A built-up disk for a telegraphone, comprisin spirally coiled steel Wire the various convo utions' of which interlock with one another, and means surrounding the coilfor 1o 7binding the convolutions into permanent engagement with one another.

1n vwitness whereof, I subscribe my signature, in the presence of two witnesses.-

JOHN A. LIEB.

Witnesses:

- WALDo M. CHAPIN,

MAY BIRD. 

